Variables related to recurrence of pleomorphic adenomas: outcome of parotid surgery in 182 cases.

Objective: We present our experience in parotid surgery for pleomorphic adenomas; analyzing a prospectively recorded database of parotidectomy; aiming to identify independent variables related to adenoma recurrence.

Study Design: Prospective case series.

Methods: Data of 182 patients; 164 new tumors and 18 revision parotidectomies were analyzed. The main outcome measure was tumor recurrence; the analyzed variables were age, gender, tumor size and site, safety margin, tumor puncture, spillage, adherence to facial nerve, surgical procedure, and follow-up period.

Results: Five new patients had a recurrence, two revision cases had second recurrence (11%), the overall recurrence rate was 3.8%. Recurrence rate was not related to age, gender, or duration of follow-up. Recurrence was related to larger tumors, tumors less than 30 mm in diameter are unlikely to recur. Tumor recurrence was inversely related to safety margin. Tumors with a diameter of 4 cm or more have no margins. All the seven tumors that recurred were punctured. Spillage was reported in five patients, four had a recurrence (80%). Tumor capsules were related to facial nerve in 75 cases; 6 of them had a recurrence (8%).

Conclusions: Tumor puncture and spillage were the only variables that have an independent effect on recurrence, 26.9% of punctured tumors and 80% of cases of spillage recurred (P = .043 and P = .035, respectively). Although tumor size, safety margin, and adherence to facial nerve are related to recurrence, logistic regression suggests that these are confounding variables influencing recurrence through effect on puncture and spillage rates.